Overview of PHENIX MuTr DST QA Software



Histogram summarizing status words for Au data.
Textfile summarizing statistics of status words for Au data.
ROOT file containing NTuple with run number and status words for Au data.


The Muon Tracker DST QA sofware is located in the CVS repository in the utils/qa/pdst directory. The code analyzes a DST and produces histograms of interesting information that one can use to help decide on the quality of the data contained in the DST. The histograms produced are:

MutSPulseSamples - Four digitized samples from the cathode pulse.
MutSCathClusWidth - Cluster width of fitted cathode clusters.
MutSCathClusQFit - Fitted charge of cathode strip clusters.
MutSCathClusQFitSt1 - Fitted charge of cathode strip clusters on station 1.
MutSCathClusQFitSt2 - Fitted charge of cathode strip clusters on station 2.
MutSCathClusQFitSt3 - Fitted charge of cathode strip clusters on station 3.
MutSCathClusQPeak - Peak strip charge of cathode strip clusters.
MutSCathClusQPeakSt1 - Peak strip charge of cathode strip clusters on station 1.
MutSCathClusQPeakSt2 - Peak strip charge of cathode strip clusters on station 2.
MutSCathClusQPeakSt3 - Peak strip charge of cathode strip clusters on station 3.
MutSNumCathClustersSt1 - Number of fitted cathode clusters per event for station 1.
MutSNumCathClustersSt2 - Number of fitted cathode clusters per event for station 2.
MutSNumCathClustersSt3 - Number of fitted cathode clusters per event for station 3.
MutSHitsPerPlaneSt1 - Average number of fitted cathode clusters for each plane of station 1. There are 48 planes in all, starting with octant 0 plane 0, ending with octant 7 plane 5.
MutSHitsPerPlaneSt2 - Average number of fitted cathode clusters for each plane of station 2. There are 48 planes in all, starting with octant 0 plane 0, ending with octant 7 plane 5.
MutSHitsPerPlaneSt3 - Average number of fitted cathode clusters for each plane of station 3. There are 32 planes in all, starting with octant 0 plane 0, ending with octant 7 plane 3.
MutSNumTracks - Number of fitted tracks per event.
MutSTrackMom - Fitted track momentum.

In addition to these histograms, two Ntuples will be written to the QA ROOT output file. They are:
MutSHotStrips - Catalog of hot strips and the hit average for each strip (percentage of events for which the strip is hit). A "hot" strip means the hit average has exceded the limits in this table:

         Au data     pp data
         ----------   ----------
Sta 1.     0.15     0.003
Sta 2.     0.10     0.00175
Sta 3.     0.05     0.0011

MutSGoodStrips - Catalog of all strips and hit averages for all strips which registered at least one hit and were not classified as hot (used to be called MutSAllStrips, but I changed it to MutSGoodStrips since it does not really contain "all" the strips).

The QA software will look at these histograms and perform checks to see if the data falls within certain limits when the dstQaSummary.C macro is run. Some limits differ for Au and pp data. The limits the data must conform to in order to be considered a good run are currently set at:

pulse sample 3 > 15(Au), 2(pp) (status bit 4)
pulse timing check: sample3-sample2 > 0 and sample3-sample4 > 0 (status bit 8)
1.75 < mean clusterwidth < 3.25 (status bit 16)
50(Au), 30(pp) < mean qfit < 100 (status bit 32)
30(Au), 20(pp) < mean qpeak < 90 (status bit 64)
0 < mean # clusters per event in sta. 1 < 192 (status bit 128)
0 < mean # clusters per event in sta. 2 < 192 (status bit 256)
0 < mean # clusters per event in sta. 3 < 128 (status bit 512)
(# dead planes on station 1 < 12.5%) && (# hot planes on station 1 < 25%) (status bit 1024)
(# dead planes on station 2 < 12.5%) && (# hot planes on station 2 < 25%) (status bit 2048)
(# dead planes on station 3 < 12.5%) && (# hot planes on station 3 < 25%) (status bit 4096)
1 < mean track momentum < 50 GeV (status bit 8192)
0% < percentage of events with tracks found < 100% (status bit 16384)

A hot plane is defined as a plane with a hits/plane/event average of > 0.1 for pp data and >5 (stations 1,2) and >3 (station 3) for Au data.

The dstQaSummary.C macro will also attempt to fit a Landau function to the qfit and qpeak distributions for each station, and the MPV (most probable value) will be written to the dstqasummary.txt file. A summary listing of all hot and dead planes will also be written to the dstqasummary.txt file.

Two files will be produced by the QA software. dstqasummary.txt provides a listing of various histogram properties, and also shows a status word. Each bit in the status word corresponds to whether the data in the DST fell within the limits stated above. The lowest order bit is an overall status bit, if any of the tests failed the bit is set to 1, if all of the tests passed the bit is set to 0. The second bit is used to flag data that might be considered "questionable" (this bit is not being used presently). The remaining bits correspond to the 13 tests stated above. For example, the 5th bit denotes whether the cluster width was within the expected ranges, the 6th bit denotes whether the mean qfit was withing the expected ranges, etc... If all the bits are 0 then the data fell within all of the expected limits.

The file dstqastatus.txt simply lists the status word.



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